María C. Apezteguía

Related factors to human toxocariasis in a rural community of Argentina

The objective of this study was to evaluate the relationship between toxocariasis frequency and demographic, environmental, sanitary variables, eosinophylia, and other intestinal parasites in a rural population of Argentina. Serological examination of 100 individuals was carried out by using ELISA technique for the detection of anti-toxocara antibodies. Eosinophiles in peripheral blood, presence of intestinal parasites, and demographic, environmental, and socio-cultural data were evaluated. Eighty-one feces samples of dogs belonging to the studied people were analyzed to detect eggs of Toxocara canis. Thirty of them were from 30 dogs and 51 were pools from dog feces. Samples of dirt from around the homes (n: 47) and from public park (n: 4) were taken. To determine the associations, the c(2) and Fisher tests were used. The seroprevalence was 23%. Eosinophilia in peripheral blood was detected in 86.95% seropositive individuals and in 37.66% seronegative individuals (p < 0.001, OR = 11.03). Of the 23 people with positive serology, 69.56% had at least one intestinal parasite. All individuals with positive serology had dogs in their homes. Among the dog owners there was a significant association between the presence of anti-toxocara antibodies and home flooding. Eggs of T. canis were detected in the feces of 5/81 dogs and three of these dogs belonged to individuals with positive serology. Eggs of Toxocara spp. were found in 41.17% of the dirt samples, eight of which came from the area surrounding the homes of individuals with positive serology (p = 0.032; OR = 4.36). Taking into account all the variables influencing the frequency of toxocariasis in this population, the implementation of Public Health programs specifically focused on anti-parasitic treatment of dogs is recommended.

Screening of the municipal water system of La Plata, Argentina, for human intestinal parasites.

The La Plata River, though severely contaminated by intestinal parasites through the discharge of tons of crude fecal material from a main sewage channel, nevertheless provides drinking water to two-thirds of La Plata, Argentina, after conventional purification at a processing plant. With intestinal parasitosis being endemic here, we investigated the importance of this water in transmitting such pathogens to the citys populace by means of standard methodology for sample acquisition and processing involving filter-concentration of waterborne particulates. Of 14 tap-water samples collected from the distribution network, 12 pertained to four zones (A-D) within the city center; while the remaining 2 were obtained near the processing plant, 15 kilometers outside the city. Although parasites were found within the samples derived from the four urban zones, none were detected in the specimens obtained near the plant. The four downtown areas differed from each other as to the quantity and nature of the parasites present in their water: whereas zones A and B registered similar lower levels of contaminants, C and D exhibited higher values significantly different from the former two and from each other. Given an average parasite count/l citywide of 0.38 and a probability of encountering a parasite within 11 of water of 0.32, the municipal network is seen to contribute to the transmission of intestinal parasites. A routine system of water-quality control is therefore needed throughout the city along with the establishment of infrastructures for locating and eliminating peripheral sources of contamination.

Participación comunitaria en el control de las parasitosis intestinales en una localidad rural de Argentina

OBJECTIVES To design, implement, and evaluate a complex plan of actions aimed at reducing parasitoses in a rural town in the province of Buenos Aires, Argentina, with the involvement of the community. METHODS The project took place in General Mansilla, Buenos Aires province, in three stages. First, the initial epidemiological situation of intestinal parasitoses in the community was assessed by analyzing for parasites a series of stool samples and anal swabs taken from a sample of 522 individuals. Second, interventions were implemented: the pharmacological treatment of the infected individuals, and health education for the public involving local promoters. Third, the pharmacological treatment was evaluated with followup stool testing for those treated; the health education effort was evaluated through a survey and stool testing for parasites of those who had participated solely in the education. RESULTS The frequency of intestinal parasitoses was 58.2%; of the total, 43.9% were protozoa and 35.2%, helminths. The most common pathogens were Enterobius vermicularis, Blastocystis hominis, and Giardia lamblia. The deworming treatment reduced intestinal parasitoses to 15.1% (P < 0.001), and was more effective in helminths than in protozoa. Intestinal parasitoses declined following the health education intervention, in general (from 58.2% to 47.9%; P = 0.019), as well as for helminths (from 35.2% to 20.3%; P < 0.001), and hygiene habits improved significantly. CONCLUSIONS Treatment of parasitosis and the educational intervention provided by local promoters made it possible to reduce parasitic diseases-particularly those caused by helminths-in the community under study. We recommend extending this experience to other rural communities and broadening the interventions to cutoff additional modes of transmission, such as water and food.

Nutritional status in parasitized and nonparasitized children from two districts of buenos aires, Argentina

The Program for the Control of Intestinal Parasites and Nutrition was designed to intervene in small communities to prevent and control the effects of parasitic infections on childrens health. Objectives: To analyze the association between nutritional status and parasitic infection in suburban and rural children from Buenos Aires, Argentina. Methods: Nutritional status was assessed by anthropometric (weight, height, BMI, skinfolds, upper arm circumference, muscle, and fat upper arm areas) and biochemical (Hb, Ca, Mg, Zn, and Cu) indicators. Parasitological analysis were made on both serial stool and perianal swab samples. A total of 708 children aged 3–11 were measured. The biochemical analysis included 217 blood samples and the parasitological study included 284 samples. Results: Anthropometric status was similar in both settings with low rates of underweight and stunting (<6%), and high rates of overweight (∼17%) and obesity (∼12%). Ca deficiency was significantly higher in suburban children where 80% of them were hypocalcemic. Around 70% of fecal samples contained parasites. Among infected children, the most prevalent species were Blastocystis hominis and Enterobius vermicularis (∼43%) followed by Giardia lamblia (∼17%). Differences in parasitological status between districts were not significant. In the suburban district parasitized children were lighter, shorter, and had a lower upper arm circumference than their non‐infected peers. No differences in anthropometric status were seen among infected and uninfected rural children. Conclusions: The results suggest an association between intestinal parasites and physical growth in suburban children. Rural children seem to be protected against the effects of parasitic infection. Am. J. Hum. Biol. 26:73–79, 2014.

Comparación de métodos de lisis y extracción de ADN de trofozoítos de Giardia lamblia

Se evaluo la eficiencia de procedimientos de lisis y tratamientos de extraccion de ADN de trofozoitos de Giardia lamblia respecto a la eficiencia de ruptura, cantidad y pureza de ADN, ademas de los tiempos de procesamiento y costos. Se testearon cinco metodos de lisis (agua destilada y calor; agua destilada, calor y proteinasa K; buffer de lisis D; buffer de lisis E y un kit comercial) y tres metodos de purificacion de ADN (fenol:cloroformo: isoamilico; Chelex 100 y un kit comercial). Los datos obtenidos se analizaron estadisticamente. La combinacion de buffer de lisis E y Chelex fue un metodo simple y economico, que produjo alto rendimiento de ADN con baja pureza. Ella tecnica comercial fue un metodo simple, mas costoso que produjo bajas cantidades de ADN con un nivel de pureza apropiado para estudios moleculares

Weight and height centiles of Argentinian children and adolescents: a comparison with WHO and national growth references

Abstract Background: Studies in several countries comparing the performance of WHO references and their own national growth standards reported differences that could affect screening and growth monitoring. Aim: To estimate weight and height centiles on a sample of Argentinian children and adolescents and compare selected centiles with WHO and national growth references. Subjects and methods: A cross-sectional school survey was conducted on 6239 boys and girls aged 5–18. Data were collected between 2005–2009 in Santa Rosa, Argentina. Smoothed weight and height centiles were estimated by the LMS method and compared with WHO 2007 and Argentinian (ARG) growth references. Results: Weight centiles were higher than those of WHO and ARG. Height centiles were above the ARG and below the WHO ones. The greatest differences with ARG were seen before puberty and then declined up to age 18. In contrast, differences with WHO increased from puberty onwards. Conclusion: Compared with the ARG reference, linear growth of these schoolchildren shows a secular acceleration without substantial improvements in the adult height. In relation to WHO, the results suggest that around the adolescent growth spurt differences in linear growth between populations became larger, limiting the clinical usefulness of international growth references in adolescents.